Numerical investigation of the effect of prepared phase change material-expanded graphite composite and vertical air ducts on the thermal performance of a Li-ion battery

Abstract

In this study, distributed cooling ducts (DCDs) and prepared phase change material-expanded graphite composite (PCM-EGC) are utilized to improve the thermal characteristics of Lithium (Li)-ion batteries which are widely used in industry. Theoretical concepts are first discussed to provide a strong basis for the topic, and numerical/simulated results are then presented to validate theoretical results. To provide a comprehensive and clear basis, three Li-ion batteries are technically compared to each other. The first one is a commonly used commercial Li-ion battery, the second one includes 19 DCDs, and the last one comprises 19 DCDs plus PCM-EGC. The following points also being the novelty and contributions of this work are demonstrated:

• Adding DCDs to a battery smoothes the temperature curve distributed across the battery’s unit cells.

• Adding both DCDs and PCM-EGC not only more smoothes the temperature curve but also significantly decreases the maximum temperature of the battery, so that, the operating point of the battery temperature shifts into the safe thermal region of the battery, which is less than $60°\mathrm{C}$ as suggested by manufacturers.